Toenail fungus, also known as onychomycosis, is a condition in which the toenails become yellow or discolored, thick, and brittle as a result of a fungal infection. Studies have shown a prevalence of this condition as high as 10-25% of the general population. 

The laser light passes through the toenail without causing damage to the nail or the surrounding skin. Unlike the oral medication, the laser does not require blood testing, has no interactions with any medications, and has no risk of liver toxicity or allergic reactions.